The IBM Personal Computer, also known as IBM PC or IBM PC Model 5150, is the name of the first personal computer released by International Business Machines Corporation (IBM) in 1981. The IBM 5150 can be seen as the progenitor of the modern PC hardware platform as it exists today. The computer became such a success already within its first months after release that it was often referred to as just “The PC”.

Dual monitor capabilities

The original IBM PC Model 5150 was equipped with an Intel 8088 running at 4.77 MHz and 16 KB memory (could be upgraded to 256KB). The PC wasn’t shipped with internal storage. However the 5150 came with either one or two 5-1/4″ floppy drives. Alternatively users could also connect their own cassette recorder via the 5150’s cassette socket. The video processor was a CGA video card with 16KB of memory which could be connected to a NTSC television set or an RGBi monitor for display. When adding an MDA adapter to the unit, the PC could be used with two monitors concurrently. The most commonly used operating systems for the IBM PC were DOS 1.0 and CP/M-86.

The convertible version of the original 5150 model

Laptop version of the IBM 5150

The number of orders for the 5150 quickly surpassed expectations of IBM shortly after launch with 40.000 units already ordered on the day of the announcement and 100.000 units by the end of 1981. By the end of the year 1983 IBM was able to sell up to 750.000 units of the 5150 surpassing the sales of the Apple II. As IBM had little retail experience it closed a deal with ComputerLand and Sears Roebuck which became the main outlets to sell the 5150 model throughout the United States.

Prices for the IBM 5150 varied depending on the system’s configuration. The basic model was available at a retail price of US$1,565 (16K RAM, Color Graphics Adapter, no disk drives). A model with color graphics and 256 kB however would have cost you around $6,000.

On April 3, 1986, IBM released a convertible version of its original 5150 model. The device weighting 13 pounds came with a monochrome CGA-compatible LCD screen and was sold at a retail price of $2,000. The IBM PC Convertible was the first IBM computer to use the 3.5″ floppy disk standard. Apart from the convertible model the IBM PC 5150 experienced many successors throughout the years such as the IBM PC XT released in 1983 or the IBM PC AT released in 1984.

Advertising for the 5150 by IBM showing a Charlie Chaplin impersonator

IBM 5150: A durable companion

Due to its longevity and robust hardware the IBM 5150 remained in-service at many enterprises and institutions. In the mid-2000s IBM PC and XT models were still in use at the majority of U.S. National Weather Service observing sites.

The 5150 was shipped with the game “Colossal Cave Adventure”, a text-based videogame developed in the mid-70s by Will Crowther and Dan Woods. The game was originally intended to be a vector map of the Mammoth Cave in Kentucky but was later developed into one of the first text adventure games of its kind.

The 5150 can be seen in the popular 80s movies Ferris Bueller’s Day Off and Strapless.